see on GitHub

Session: Querying: How to Query With Exact Match

By default, the whereXXX() methods in query use a case-insensitive match.

To perform a case-sensitive match you should use the exact parameter.

Syntax

query.whereEquals(fieldName, value, [exact]);
query.whereNotEquals(fieldName, value, [exact]);

// ... rest of where methods

Parameters
fieldName string Object field to use
value any Predicate value
exact boolean Indicates if predicate should be matched in case-sensitive manner

Example I - Query With Exact Match

// load all entities from 'Employees' collection
// where firstName equals 'Robert' (case sensitive match)
const employees = await session.query({ collection: "Employees" })
    .whereEquals("FirstName", "Robert", true)
    .all();
from Employees where exact(FirstName == 'Robert')

Example II - Query With Inner Exact Match

// return all entities from 'Orders' collection
// which contain at least one order line with
// 'Singaporean Hokkien Fried Mee' product
// perform a case-sensitive match
const orders = await session.query({ collection: "Orders" })
    .whereEquals("Lines[].ProductName", "Singaporean Hokkien Fried Mee", true)
    .all();
from Orders 
where exact(Lines[].ProductName == 'Singaporean Hokkien Fried Mee')